Screening and separating machine



Nqv. 10, 1925. 1,561,031

J. T. slMFssoN SCREENING ND SEPARATI'NG MACHINE Filed Dexc. 10. 19423 V3 Sheets-Sheet l1 i @Wam @y (fll Nqv. 10 1925- vJ. T. SIMPSON scmENING AND SEPARATING MACHINE Filed Dc. 10, 1923 5 sheetsQsnet 2 J. T. SIMPSON SCREENING AND SEPARATINGMACHINE Filed Dec; 1o. 192s s sheewsnet s a Z/ Z2 lllatentecll Non., lill, l5.

JOSEPH T. SIMPSON, OF CHICAGO, ILLINOIS.

SCREENING AND SEPARATIN Gr MACHINE.

application filed Deeeinber 1o, 1923. seriai No. $9,539.

To all whom t may concern:

Be it known that I, JOSEPH 'I. SIMPsoN, a citizen of the United and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Screening and Separating Machines, of which the following is a-speciication.

My invention relates to screening and separating machines, and has for its object improvements in devices of that character. More particularly the object is to provide a superior device for cleaning and reclaiming sand once used-in making castings so that the cleaned sand may be used over again for additional casting purposes.

' In foundry practice it is desirable to have the sand of large grains and free from` foreign material when used to make` molds for castings. In making molds, the ramnnng oit the sand crushes someparts to dust, and -in the making of castings, the heat of the metal disintegrates the sand with which it come in. contact, and the consequent dust permeates the body of the remaining sand. In the mixing process of preparing sand for -use in molds, the sand grains are coated with clay or other bonding material. In the casting process, this bonding material is destroyed .tor bonding purposes bythe heat of the hot metal, but adheres to the grains ot sand. One of the main objects ot' the present invention is to free the grains ot 'sand from this destroyed bonding material so that the clean sand grains may be again coated with new bonding material and be used again in the'making of other castings. Also, when castings are removed troni the mold, much of the sand is in lumps.

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Another ot the main objects of the present machine is to break up these lumps, and to separate the large grains of sand from dust and tailings.

In the accompanying drawings- Fig. 1 is an elevation;

Fig. 2 is a central section partly in elev vation, at right angles to Fig. 1; and

Figs. 3 and 4 are sections on lines 3-3 and l-4, respectively, of Fig. 2.

Standing on the Hoor or other base are two standards lland 12 which support the entire apparatus. At their upper ends these standards are secured to a beam 13, or other part of the building within which the machine is located. Connected to these stand- States of America,

ards are cross beams 14 and 15 which carry to the lower edgeof ring is a sheet metal y cone 26V which surrounds the screen 22 at some distance. therefrom. The lower end of cone 26 terminates in a spout 27, and the y spout 23 extends thru the wall of thevcone 26 as shown in Fig. 1.

On the lowerend of the shaft 18 is ahead 28, and on this head are fan blades 29. The upper parts of these blades are located within the ring 20, and the lower parts are in the cone 22. The shape of the outer edges of the bladesv corresponds in general with the shape of the ring 20, and are of about the size and shape indicated in Fig. 2. .Be--

Vtween the blades 29 and secured thereto by 31 set in an 111-.

angle irons 30, are plates 24 is ring 25, and secured to this I clined direction so that taken together they form a cone thru which the blades 29 pro- ]ect.

The upper end of the ring 25 is closed by i a cover 32 which has a central, opening and over this opening is a hopper 33. The cover 32 and hopper 33 arev in two parts secured together by flangesv 34 and bolts `35. A pipe 36`having-a branch 37 is connected thrutwo points .in the cover with the in terior, of the ring 25 and outsideof the ring 20. The outer end of pipe 36 is connected in the ordinary way to anexhaust fan.

Inside of the cone 26 and overthe spout 23 is a piece of sheet metal 38 which serves of spout 23.

In operation a belt connected vto pulley 39 only to keep material from piling up on top 10o drives the shaft 18 and fan 29 at high speed.

With the exhaust fan in operation, air flows inward thru the hopper 33,` the fan 29 and,

screen 22 to the space around the screen. 105

From here it flows upward thru the annular space between rings 20 and 25 and thence thru pipe 36 to the discharge of the exhaust fan.

While this is in operation, used material n o from the foundryY is shoveled into the hop per 33 and falls on the fan 29. liumps ol sand thus falling,r on the fan are hurled outward with 2L'reat force against the inner face of the rincr 2G, and then fall downward. The ringn Q0 is in fact abreaker ring. The material irst reaches the ian at near its central portion, and as it moves outward under the action of the blades, its velocity increases until it is thrown against the ring with a velocity equal to that ot' the outer edges ol' the blades. In this operation` the plates 3l prevent material from falling: from the hopper thru the fan without being hurled against the breaker ring' 20. At the same time the plates 3l leave the lower conical part of the fan free to operate over the adjacent screen surface.

From the breaker ring; 20 the material moves downward to and over the screen 22. That part of the material which is fine enough to pass thru the screen falls into the cone 26, while the tailings pass outward thruthe spout 23. Accompanyingv this How of material thru the screen is a flow of air which also enters thru the hopper. It is to be observed that the diameter of the fan 29 is greater than the diameter at the bottom of the hopper 33, and as a consequence there will be such a flow ot air thru the hopper and the screen, even when there is no exhaust applied to pipe 36. The intention is,

however, to have exhaust applied to pipe 36 for the purpose of removing dust from the sand and conveying' it away. In this process the air flows thru the screen and then turns upward, carrying the dust with it. The heavier particles of sand fall downincassi ward and pass thru the spout 27 to any con venient receptacle.

hen air is forced thru the screen as above described, it loosens the sand up, or aerates it as the term is used in foundry practice. This is a desirable result which is produced by this construction.

l. Ih a machine of' the class described, a Vtan and means for driving itt a fan chainber having its lower portion consisting ol' a conical screen, a conical casing surrounding the fan chamber and removed a short distance therefrom` discharge spouts for the chamber and the casing' at the apexes thereof, and an exhaust'pipe connected to the upper part of the annular space between chamber and casing.

2. In a machine of the class described, a breaker ring7 a conical screen connected to the lower edge of. the ring and terminating in a central spout, a cover for the ring and provided with a central opening, a fan located in the ringr and screen and havingy the outer edges of its blades corresponding r to the shapes of the ring and screen, and inclined partition plates located between the blades of the fan.

3. In a machine of the class described, a chamber having its lower portion consistingr of a conical screen, a fan located in the chamber and having' the lower portion ol its blades tapered to correspond to the conical form of the screen, and partitions between the blades and intermediate between the upper and lower portions thereof.

Jessen r. srMPsoN. 

